Police Chief Joel Bryden said Tuesday that he would send more officers downtown to check on the bars on Friday and Saturday nights.

Police are hoping the beefed-up presence will help prevent brawls such as those that occurred early Sunday.

That morning, nine people were arrested, two hospitalized and three police officers injured in several drunken fights outside of bars on Locust Street, according to police.

In recent months, police have seen an alarming increase in violence that has escalated from the minor physical altercations that tend come with weekend bar crowds, the chief said.

“The thing that concerns me is that they’re becoming bigger and more violent, and we need to put a stop to it before someone gets seriously hurt or killed,” Bryden said.

He said the upswing in bar brawls stems from several factors, but he largely faulted establishments that over-serve alcohol.

“We want to work with the bars and we want to work with the businesses downtown to make it safe,” he said. “It’s their responsibility to not serve drunk patrons … and we are going to hold businesses accountable when they break they law, just like individuals.”

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